cook pasta. drain. set aside.
cook pasta sauce with beef however you like.
i usually do my regular bolognaise sauce which involves alot of onions, garlic, fresh tomatoes, parsley, herbs, etc and i usually throw in a bit of ricotta or romano cheese in to add some more flavour. set aside.

melt butter in a large pot. add flour and stir until mixed and golden.
add milk and mix. wait until it boils.
mix eggs together lightly and add to pot. let boil. turn off heat.
add Parmesan cheese.
add salt and pepper to liking.

layer the bottom of an over proof dish with some beshamel sauce.
add a layer of pasta.
add layer of the bolognaise sauce.
add another layer of beshamel sauce....

keep going until you have run out of either food or room.
finish off the last layer (try to make the last layer from beshamel sauce) by covering it in shredded mozzerrella cheese.
put it in the oven and cook until the cheese becomes golden.

NOTE:
some people dont use eggs in the beshamel sauce but i find it adds a beautiful thickness and texture to it. i always cook it with eggs, otherwise you can get a beshamel in varied degrees of sloppiness. it doesnt taste nice, trust me, especially when the sauce is slightly watery.